* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html,body{
    width: 100%;
    height: 100%;
}
.nav{
    height: 50px;
    width: 100%;
    color: white;
    background-color: rgba(144, 141, 141, 0.5);

    display: flex;
    justify-content: center;
    align-items: center;
}